X0306 4 2021-01-19 0 0001478320 Adaptive Biotechnologies Corp ADPT 0001780664 RUBINSTEIN JULIE C/O ADAPTIVE BIOTECHNOLOGIES CORP. SUITE 200 SEATTLE WA 98102 0 1 0 0 President Common Stock 2021-01-19 4 M 0 15000 6.32 A 15000 D Common Stock 2021-01-19 4 S 0 2563 68.72 D 12437 D Common Stock 2021-01-19 4 S 0 7415 69.54 D 5022 D Common Stock 2021-01-19 4 S 0 4822 70.51 D 200 D Common Stock 2021-01-19 4 S 0 200 71.23 D 0 D Common Stock 2021-01-20 4 M 0 15000 6.32 A 15000 D Common Stock 2021-01-20 4 S 0 4366 66.49 D 10634 D Common Stock 2021-01-20 4 S 0 4264 67.58 D 6370 D Common Stock 2021-01-20 4 S 0 6370 68.34 D 0 D Stock Option (Right to Buy) 6.32 2021-01-19 4 M 0 15000 0.00 D 2025-06-09 Common Stock 15000 215000 D Stock Option (Right to Buy) 6.32 2021-01-20 4 M 0 15000 0.00 D 2025-06-09 Common Stock 15000 200000 D The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 20, 2020. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $68.03 to 69.00, inclusive. The reporting person undertakes to provide to Adaptive Biotechnologies Corporation, any security holder of Adaptive Biotechnologies Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in any footnotes to this Form 4. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $69.06 to 70.00, inclusive. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $70.07 to 71.00, inclusive. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $71.20 to 71.25, inclusive. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $66.05 to 67.00, inclusive. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $67.09 to 68.02, inclusive. The price reported for this transaction is a weighted-average price. The shares were sold in multiple transactions ranging from $68.25 to 68.73, inclusive. The option is fully vested and exercisable. /s/ Julie Rubinstein by Eric Billings, attorney-in-fact 2021-01-21